Referenced by Selection: Main Roads from Philadelphia to New York and Washington, 1804 Your Browser doesn't support iframes. Geographic Area Covered: Pennsylvania--Philadelphia, Pennsylvania--Philadelphia Region, Washington (D.C.), Washington (D.C.) Region, Maryland--Baltimore Region, Maryland, Delaware Geographic Coordinates: (W 75°32'08"--W 75°11'43"/N 39°57'03"--N 39°48'09') View on Google Maps